1. Field of the Invention
This invention relates to a process for coating and an apparatus therefor, and more particularly to a process for coating to produce a coated film of a uniform thickness and uniform property, and an apparatus therefor.
2. Description of the Prior Art
Heretofore, there have been known various processes for forming coated films such as by using a brush, by spraying, and by dipping in a liquid coating material and the like. However, in these processes it is essential to use a technic of a higher level for the purpose of producing a coated film of a highly uniform thickness and in particular, it is very difficult to produce a very thin film of a uniform thickness. For example, when a member to be coated is dipped in a vessel containing a coating material and then pulled out to form a coated film on the surface of the member to be coated, the composition of the coating material and its concentration distribution in the coating material should be kept always constant to produce a coated film of a uniform thickness. Contamination of external impurities also should be avoided. It addition, unevenness of thickness of the coated film, which is caused by nonuniform flowing-down of the coating material applied to a member to be coated, should be prevented. Therefore, an elaborate and high-level technic is required to take care of the above mentioned conditions and thereby the coating procedure becomes very complicated.